Hi, welcome. it could be a tyre problem, theres a few threads on here that refer to tram lining which seems worse with some brands of tyres, have a search for tyres which should pull up some of the threads which may give you some more information on other owners experiences with handling

Personally I don't mind it, once you know its there you (should I say I) just accept it. The car itself never loses grip unless you are really really daft with it. I just put it down as one of the great little traits of these cars.

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You have the same as my silver one and thats the one I have that does it (the M versions have many different components that together mean they don't do it). I guess it all depends on budget and time/ability to tinker. Most jobs on these cars can be done without taking it to the garage if you search for it or even just ask. Everyone on here has done something to their cars and everyone will lend a helping note to get you to do anything you want.

My 1998 2.8 has 64k miles on the clock and apart from a strong strut and a butt strut is, as far as I am aware all original underneath. It has Falken 451's which were fitted when I bought the car 2 years ago and it has never suffered from any tramlining.

My 1.9 P Reg was very poor especially on uneven narrow country roads where I had to slow down to let oncoming traffic pass! In my imperfect understanding of the problem (after 5 months of mixed driving) there are about 4 or 5 joints/bearings & any looseness builds up in the system so changing one component may solve 90% of the problem but might just reduce some movement. Ive had a new track control arm fitted which made some improvement but also new Uniroyals & they have improved about 90% of problem, I can now do 60 on my lanes & overtake where possible! But as mentioned above - I'm now slightly nostalgic for the way it drove before when you had to watch it when bumps appeared & welly it when it pointed in the right direction - great fun when used to it. Have kept old tyres & may change them back sometime -just for the fun

Mines a 2001 Sport and I notice the tramlining gets worse as the tyres wear. I've always had Falken's fitted and had a new pair fitted recently and was surprised in the difference it made, I guess as the tyres wear gradually I just get used to it and adjust accordingly. Saying that the tramlining is never excessive and adds an extra dimension to the driving experience when it does happen!

Just to add that if you only had the passenger side arm done, then I'd recommend getting the drivers side done as well since that is likely to be worn, if not quite as badly as the passenger one. Of course it may have been replaced more recently, but since the Z3 is known for issues such as tramlining, then IMHO it's better to give it the best chance by replacing parts in pairs. FWIW I replaced my bushes with Powerflex ones, new drop links and I got a strut brace off the classifieds. I also swapped the tyres around from Michelins on the front to the Avons I originally had on the back and it seemed less prone to tramlining.

However, as Z3 owners I think we have to accept that our cars aren't exactly the last word in handling finesse and just enjoy them for what they are once the basic servicing/maintenance has been done.

Hi, like others have said this is called tramlining. It is most commonly caused by worn and hardened tires. I had exactly the same issue just two weeks ago until i got new tires. Now perfect. I also hoisted the car just prior to getting the new tires and it was like new under there. Dont stress just get new tires if your current ones are worn or old. Just remember someone paid a lot of money for these cars brand new and bmw would have a bad name if tramlining is to be expected.

If the car is losing traction on a bumpy service this might be the shock absorbers i.e. the wheel is bouncing up and down too long and so is not in contact with the road. Many Z3s, because of their age, will have “tired” shock absorbers.

If you feel the front wheels following ruts and low points (sometimes even the painted lines) on the road then that would most probably be “tramlining” to which many Z3s are susceptible. Tyre changes seem to be the main cure.

As said above, if you have changed the lower control arm rear bush on one side, it is generally good practice to do the other side so that there is consistent stiffness across the axle.

The other thing that's made a huge difference in fitting 17" wheels. It has transformed the car for me. I can now feel what is happening, whereas on the 16s, the handling was vague and not confidence inspiring.

The biggest difference in handling is through fitting new tyres. Once the tyres start to wear the tramlining gradually increases. If you change the tyres and you still have issues, then start looking at bushes and other suspension components. Whilst I am prepared to accept that bushes, strut braces and other such things will improve handling and likely help make tyre wear more even, thus delaying the tramlining coming back, if you make these changes on old rubber, you really aren't going to get the benefit. The same argument goes for 16" and 17" wheels - unless you are comparing new rubber with new rubber, you really can't say that the car handles better on 17" wheels - if you are going from old rubber to new rubber the car will feel better regardless of the change in rim size. The lower profile tyres on the 17" wheels will have less lateral movement, which should improve handling, but they will have less give, so they will be less comfortable on uneven roads.

Robert T wrote:The biggest difference in handling is through fitting new tyres. Once the tyres start to wear the tramlining gradually increases. If you change the tyres and you still have issues, then start looking at bushes and other suspension components. Whilst I am prepared to accept that bushes, strut braces and other such things will improve handling and likely help make tyre wear more even, thus delaying the tramlining coming back, if you make these changes on old rubber, you really aren't going to get the benefit. The same argument goes for 16" and 17" wheels - unless you are comparing new rubber with new rubber, you really can't say that the car handles better on 17" wheels - if you are going from old rubber to new rubber the car will feel better regardless of the change in rim size. The lower profile tyres on the 17" wheels will have less lateral movement, which should improve handling, but they will have less give, so they will be less comfortable on uneven roads.

Cheers R.

I can say that Robert. I went from 16s with new rubber to 17s with old rubber. In fact the fronts on the 17s almost need replacing, and I only made the swap 3 weeks ago.

I currently have 19" wheels, original type wishbone rear bushes and decent tyres with no tram lining. .....

my experience with curing tramlining was this:

I tried all sorts on my first 3.0 Z3 to cure it, it had 18" wheels on it,
I fitted a strut brace, no difference to tramlining but stiffened the car up,
New springs and shocks, no difference to tramlining,
Purple poly bushes on the rear of the wishbones, seemed to exaggerate it and made my fillings rattle.
Increased tyre pressures no difference
Decreased tyre pressures no difference
Swapped front and back wheels over and it instantly disappeared.
the problem was the front Pirelli tyres, once the rear avons were on the front it went completely.

I have a 98 M44. I have replaced all of the bushes in the suspension, drop links and control arms. All are OEM with the exception of the rear subframe side bushes in which I have used poly bushes. It had huge Mtech wheels on when I bought it but I have gone back to the original 15" pepperpots. The tires on the back are well worn Nangkangs and the fronts are low to mid range budgets (Enduros). It now handles like a dream, rides more comfortably, doesn't tramline at all, drives in a straight line - hands on or off the steering wheel. It is still on the original steering arms etc at 100,000 miles and I haven't had anything done to the steering geometry. The Mtechs looked nice but were totally the wrong wheel for the set up on my car at least. It is still on the original shocks too.

Seventeen inch wheels use tyres with a lower aspect ration - which have shorter and therefore more rigid sidewalls. These will pass a greater lateral load into the wishbone, which is (not very well) resisted by the wishbone bearings. The standard type of rubber pivot bush at the rear will of course deflect sideways a lot, and so impart an unwanted steering input to the wheels - hence the tramlining.

This is why BMW fitted almost solid rubber bushes to the M series cars which are fitted as standard with lower-profile tyres, and one of the reasons why the M roadster does not suffer from tramlining. Likewise, going from 17 to 15 inch wheels means that the sidewalls are higher and more flexible, and can therefore absorb the loading without passing it on to the suspension.

If everything else looks OK, fit poly bushes and see what happens - it is a cheap modification - but do not put up with tramlining and convince yourself that it is 'character' etc, as it is an untidy, tiring, and potentially dangerous trait.

the fact when the road is slightly uneven (like most in england!) it is very hard to keep control and the steering just jumps all over the place.

Tramlining or not tramlining

My E36 318is and E46 330i msport tramlined like pigs. My current E91 330d msport does not even hint at it whatsoever. Perhaps good rubber...Bridgestones all round from when I picked it up four years ago from Mr Sytner.....not cheap though!

My '97 2.8 did suffer a little but fitting new Falken 453's, new track rod ends plus purple Powerlex on the wishbones, I reckon I have that sorted.

BUT......although I don't get the telltale steering wheel 'snatch' of tramlining, I do still get a kind of body shudder through the wheel and car on rough or badly repaired roads, mainly at slow speed. I have been told it could be due to lack of rigidity within the chassis, but I'm afraid I'm not sure if in fact this is the case.

All I am trying to say is that there might be other causes of bad handling other than the curse of BMW's tramlining.

It is well known and accepted that the larger the wheel the more stable the ride, but at the cost of comfort. Larger wheels will require lower profile tyres, which don't have the added suspension effect of a higher profile tyre. IMO the optimum wheel size on the non M Z3's is 18" with a lower profile tyre. There is no tramlining even with the somewhat flexible OEM suspension bushes on the 2.8's.

I have moved in the opposite direction, removed my larger wheels and gone back to the original 15s wow handling is errr normal (when I say normal I mean non bmw like) after removal of the 16s I noticed wear on the inside 3rd of all 4 tyres, original size is 205 60 (or 55, cant remember now) r15, the ones removed are 225 50 r16, think maybe the 225 is too wide. the sticker in the door for tyre pressures does list both 205 and 225 so is it possible the cars fitted with the 225 option had there camber adjusted at the factory? could it be possible that all the tramlining cars were originally fitted with the 205 but have since been changed to the larger 16s with wider tyres

it feels safer now, but im now cornering harder

oh yes, also the rubber bushes go soft after just a handful of years, I swapped to polly bushes but although it did improve things it wasn't till I swapped back to the 15s that I noticed the wow factor of these bushes.
in order to tramline I would have thought the lower arms would have to move about, there does need to be some movement here but too much movement would allow the car to wonder, to little and the steering would tend to snatch.
fitting new tyres seems to be most peoples answer to this, im thinking this only works as the tyres are not yet worn and as such not all the tyre is under normal load, if you see my earlier observation on all 4 being worn on the inside edge more than the rest of the tyre gives you an idea of my line of thought. maybe different tred patterns behave in a similar way, this isn't backed up by any science, just my personal observation.
it would be interesting to build a spread sheet of everyones wheel, tyre sizes and how much each car tramlines and what the car would have been fitted with originally. some cars with the original 16s may not have had these wheels fitted when new.
as chiefy pointed out, his car handles like mine now its back on the original wheels

I don't think my 3.0i tramlines to any great extent ie following road contours. However it is slightly erratic on bumpy roads.
My Lotus Elan had the same problem after its rebuild, and Lotus called it bump steer and could be and was be completely eliminated by shimming up the steering rack. Don't know if this would be possible on a z3, but will look.
Flight

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"